Study: Bait shops spread amphibian disease

ARLINGTON, Va., April 9 (UPI) -- Biologists say they've determined western U.S. bait shops are the likely source of the spread of pathogens in salamander larvae used as live bait.

The researchers said the bait, called waterdogs, are the larvae of tiger salamanders and are used in freshwater fishing.

But James Collins, assistant director for biological sciences at the National Science Foundation, and Angela Picco of the U.S. Fish and Wildlife Service, discovered salamanders in bait shops in Arizona, Colorado and New Mexico are infected with ranaviruses, and those in Arizona with a chytrid fungus called Batrachochytrium dendrobatidis.

"These diseases have spread with the global trade in amphibians,'" said Collins. "The commercial amphibian bait trade may be a source of 'pathogen pollution.'"

The research showed 26 percent to 73 percent of fishers used tiger salamanders as bait; 26 percent to 67 percent of anglers released tiger salamanders bought as bait into fishing waters; and 4 percent of bait shops put salamanders back into the wild after the waterdogs were housed with infected animals.

In 2006, ranaviruses were detected in the tiger salamander bait trade between May and October in Arizona, New Mexico and Colorado but weren't found in the bait shops sampled in Nebraska and Texas.

The research appeared in the journal Conservation Biology.